Engineered for vocal performances onstage
Handheld vocal microphones have a certain look for both historical reasons as well as for the fact that they need to meet certain audio needs. Having a steady handgrip and controlled wind- and pop-suppression is exceptionally important.
Both of these basic needs require space in and on the unit, so companies must ensure that the shape of the vocal microphone is ergonomically-designed for the average hand. For most efficient wind- and pop-suppression, the furthest distance of the internal diaphragm from the mouth as possible is ideal, which requires a certain grill size. At the same time, the overall size of the stage vocal microphone must be bigger than a small diaphragm condenser recording microphones and smaller than a large diaphragm cylinder "bird cage" studio microphone. For the performer, it should also appear to be large enough to "hide" behind (like having an instrument), but also small enough to provide a view that enables them to move around the stage and the audience to see them.
A handheld microphone is generally held in the performer’s hand and / or secured on a mic stand. This mic is most commonly used to pick up the human singing voice in a wide variety of settings and is generally what a person visualizes a microphone to be. Moreover, if you ask a child to draw a microphone, she will most likely draw the legendary "ice cream cone shape", which is common, but not the only shape used.